Stockholders' Equity - Common and Preferred Shares - Fair Value Measurements on Recurring and Nonrecurring Basis (Detail)	6 Months Ended
Jun. 30, 2014
September 2013 Private Placement Warrants [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	0.24%
Expected life (years)	1 year 10 months 24 days
Expected volatility	79.00%
Dividend yield	0.00%
April 2013 Private Placement [Member] \| Private Placement Series A Warrants [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	0.24%
Expected life (years)	2 years 3 months 18 days
Expected volatility	87.00%
Dividend yield	0.00%
April 2013 Private Placement [Member] \| Private Placement Series B Warrants [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	0.24%
Expected life (years)	1 year 10 months 24 days
Expected volatility	87.00%
Dividend yield	0.00%

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Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

+ Details

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

+ Details

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